Apparatus for positively displacing fluids



April 28, 1970 L. w. GOLDBERG 3,508,685

APPARATUS FOR POSITIVELY DISPLACING FLUIDS Filed Aug. 16, 1966 INVENTOR.

LLOYD W. GOLD BERG ATTORNEYS United States Patent 3,508,686 APPARATUS FOR POSITIVELY DISPLACING FLUIDS Lloyd William Goldberg, Clifton, N.J., assignor to Thiokol Chemical Corp., Bristol, Pa., a corporation of Delaware Filed Aug. 16, 1966, Ser. No. 574,491 Int. Cl. B67d 5/42 US. Cl. 222135' 4 Claims ABSTRACT OF THE DISCLOSURE Disclosure relates to a tank for storing liquids having a partition for dividing the tank into separate chambers with a predetermined volume ratio and flexible diaphragms in the chambers which may be flexed by admitting gas under pressure to one side thereof to deliver liquid at the opposite side through outlet ports. The edge of each diaphragm is attached to the tank wall so as to provide the same area of tank wall and partition at opposite sides of the diaphragm as the area of the diaphragm itself. In the illustrated embodiment the tank is spherical and the partition is in the form of a spherical segment.

This invention relates generally to positive displacement, liquid expulsion systems in which a diaphragm or bladder is attached to a liquid containing tank and propelled by a pressurizing medium through the tank to expel the liquid, and relates more particularly to such a system for integrated tankage containing two (usually different) liquids.

Apparatus of this type in particularly useful in aircraft fuel systems and particularly in connection with packaged liquid rocket engines wherein it is important that the tankage be light in weight and that a maximum percentage of the stored liquid or propellant be expelled.

Accordingly, the main object of the resent invention is to provide an improved positive displacement, liquid expulsion apparatus in which the tankage is integrated so as to be of minimum weight, and the liquid expelling bladders are so arranged therein as to ensure a maximum of liquid expulsion.

An important object of the present invention is to provide an improved liquid expulsion apparatus of the type described in which the integrated tankage stores the liquids in a predetermined volume ratio.

Another important object of the present invention is to provide an improved liquid expulsion apparatus of the type described which will be safe in use in that multiple malfunctions must occur before the stored liquids (propellants) can intermix.

Other objects and advantages of the invention will become apparent during the course of the following description.

In the drawings there is shown one embodiment of the invention. In this showing the figure is a central, crosssectional view thereof.

Referring to the drawings, numeral designates the integrated tankage as a whole and includes a partition 12 which divides the interior of the tank (tankage) into two liquid compartments 14 and 16 which may respectively be for an oxidizer and a fuel, having outer walls 18 and 20. The tank is shown as spherical although it could be toroidal, and is indicated has a radius R.

The outer walls 18 and 20 of the liquid (propellant) compartments 14 and 16 are each provided with discharge outlets 22 and 24 through which the liquids (oxi dizer and fuel) are expelled by bladders 26 and 28 respectively, to be described, when acted on by a pressurizing medium such as gas admitted respectively to inlets 30 and 3,508,686 Patented Apr. 28, 1970 32. The discharge ports may be provided with a burst disc, etc., 34 and 36.

The partition 12 is a spherical segment which also has the radius R as indicated and divides the tank 10 into a predetermined ratio in which the tank compartment volume 14 is greater than the tank compartment volume 16 inasmuch as the amount of oxidizer required always exceeds the amount of fuel used.

The tank 10 is provided with four encircling manifolds 37, 38 and 39, 40, the pairs of which are fixed respectively at 42 and 44 to the walls 18 and 20 in the compartments 14 and 16. These manifolds are structurally sound and leakproof and two of these, 38 and 40, have a dual function as will be described.

The bladders 26 and 28 which may be metallic or some type of plastic such as tetrafluoroethylene (sold under the trade name Teflon) depending upon the fluids in the integrated tank and the temperature conditions, and are welded or bonded to the walls 18 and 20 between the manifolds at 42 and 44. It is to be noted that the radius of the bladder 28 is the same as that of the spherical partition 12 which is R or the same as that of the tank 10 (and the wall 20). Thus, almost equal surface area of the bladder 28 is provided in either the liquid storage or liquid expelled position.

This is similarly accomplished by the bladder 26, which being larger, is provided with the extra spherical segment area A so that before or after this area has moved to the position of area B, the remaining area of the bladder 26 is equal to the partition 12 and to the area of the wall 18 minus the areas A and B. Inequalities in the surface area caused by other aspects of the geometry of the apparatus are compensated for by proper design of the manifolds.

The manifolds 38 and 40 have communication with the pressurizing gas inlets 30 and 32 respectively which may be provided with a common source, and the mani folds distribute the pressurizing gas evenly about the circumference of the bladders 26 and 28 and between them and the spherical partition 12. The second function of the manifolds 38 and 40 which is also the function of the manifolds 37 and 39, is to provide a smooth contour for the bladders 26 and 28 to fold over in their liquid storage position or in the liquid expelled position.

In operation, the pressurizing medium is admitted to the tank 10 by Way of the inlets 30 and 32 to fill the spaces between the bladders 26 and 28 and the spherical partition 12 and move them away from it toward the tank walls 18 and 20 to expel the oxidizer and fuel from the compartments 14 and 16 through the discharge ports 22 and 24 when the built-up pressures burst the discs 34 and 36.

Due to the radius R employed in the bladders, partition and outer walls, the bladders move from a position flat against the former to a position flat against the latter. This is an important feature of the invention inasmuch as it provides for an expulsion efliciency of the apparatus of substantially It is to be noted that multiple malfunctions of the apparatus must occur before the two liquids (oxidizer and propellant) may contact each other, this safety feature residing in the fact that at least one bladder and the partition must fail before intermixing can occur. It will be appreciated that the principles of the invention are also applicable to a cylindrical tank having an arcuate partition.

What is claimed is:

1. The combination with a liquid expulsion tank having a partition dividing it into two compartments each having a discharge port in its outer wall and a pressurizing gas inlet adjacent the face of its partition wall; of a flexible bladder mounted in each compartment with its outer edge attached to the tank wall and sealing the liquid therein from said gas inlet, said bladders conform- 4. The combination recited in claim 1 wherein said ing with the opposite sides of the partition and being tank and partition are spherical.

movable toward said discharge ports to expel the liquid therefrom upon the admission of pressurizing gas through References Cited {he gas nlets, and said partition being of a shape and so 5 UNITED STATES PATENTS ocated 1n the tank relative to the attached edge of each diaphragm as to provide substantially the same surface 3,202,326 8/1965 Young 222' 386'5 area of wall at each side of the attached edge of each 3,296,803 1/1967 Kroekel 60 259 diaphragm as the surface of the diaphragm.

2. The combination recited in claim 1 wherein said 10 VERLIN PENDERGRASS Primary Exammer partition divides the tank into compartments having a US Cl XR predetermined volume ratio. 222 386 5 3. The combination recited in claim 1 wherein the walls of the tank forming the compartment and partition are arcuate. 15 

